ATA5824-PLQW Atmel, ATA5824-PLQW Datasheet - Page 11

• Manufacturer Part Number: ATA5824-PLQW
• Description: IC TXRX UHF ASK/FSK 48QFN
• Manufacturer: Atmel

Specifications of ATA5824-PLQW

• Frequency: 433 ~ 435MHz; 866 ~ 870MHz
• Data Rate - Maximum: 20kbps
• Modulation Or Protocol: ASK, FSK
• Applications: RKE, TPM, Security Systems
• Power - Output: 10dBm
• Sensitivity: -116dBm
• Voltage - Supply: 2.15 V ~ 3.6 V or 4.4 V ~ 5.25 V
• Current - Receiving: 10.5mA
• Current - Transmitting: 10.5mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 48-VQFN Exposed Pad, 48-HVQFN, 48-SQFN, 48-DHVQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -

7.2
4829D–RKE–06/06
Input Matching at RF_IN
A low-IF architecture is also less sensitive to second-order intermodulation (IIP2) than direct
conversion receivers where every pulse or amplitude modulated signal (especially the signals
from TDMA systems like GSM) demodulates to the receiving signal band at second-order
non-linearities.
The measured input impedances as well as the values of a parallel equivalent circuit of these
impedances can be seen in
of these impedances to the source impedance of 50 .
Table 7-1.
The matching of the LNA Input to 50 was done with the circuit according to
the values of the matching elements given in
board layout parasitics. The measured typical FSK and ASK Manchester code sensitivities with
a Bit Error Rate (BER) of 10
These measurements were done with multilayer inductors having quality factors according to
Table
and 0.7 dB at 868.3 MHz. These losses can be estimated when calculating the parallel equiva-
lent resistance of the inductor with R
10 log(1+R
With an ideal inductor, for example, the sensitivity at 433.92 MHz/FSK/20 Kbit/s/
±19.5 kHz/Manchester can be improved from
depends on the values in the registers of the control logic which examines the incoming data
stream. The examination limits must be programmed in control registers 5 and 6. The measure-
ments in
according to
Figure 7-1.
–
10 dB. Note that value changes of C
7-2, resulting in estimated matching losses of 0.8 dB at 315 MHz, 0.8 dB at 433.92 MHz
Table 7-3
In_p
f
433.92
RF
868.3
Table 14-3 on page
315
/MHz
/R
Measured Input Impedances of the RF_IN Pin
Input Matching to 50
loss
).
and
Table 7-4 on page 12
Table
-3
are shown in
60.
7-1. The highest sensitivity is achieved with power matching
C
1
loss
1
Z
L
(44-j233)
(32-j169)
(21-j78)
1
and L
In
(RF_IN)
= 2
Table 7-3 on page 12
Table
–
105.5 dBm to
1
are based on the values of registers 5 and 6
4
may be necessary to compensate individual
ATA5823/ATA5824
RF_IN
7-2. The reflection coefficients were always
f
L
ATA5823/ATA5824
–
Q
106.7 dBm. The sensitivity also
L
and the matching loss with
and
1278 //2.1 pF
Table 7-4 on page
925 //2.1 pF
311 //2.2 pF
R
In_p
Figure 7-1
//C
In_p
and with
12.
11